3.3 Version Control Labs

You can choose to enable the versioning of your bucket. Once you enable versioning for this bucket, it cannot be removed, it can only be disabled.

If you enable the versioning of your bucket, when you upload an object which has same name with your previous object to your bucket, you will get two versions of this one object. The old version will not be overwrite, you can access two versions of this one object. So if you update large files frequently in a versioning enabled bucket, you need some life-cycle management, so that put some old versions and files to archive, otherwise you will spend a lot of storage spaces, because the actual size of one object is the sum of all its versions. For each different version, their E-tags are different, but their link address is same.

You can delete a version of the object, and it cannot be restored. You can delete the object as well, and it can be restored. You just need to delete the "delete marker" of this object. The restoring actually takes advantage of the Glacier, it has nothing to do with the object itself.

Multi-factor authentication (MFA) delete capability: You can add an extra security step which is called Multi-factor authentication delete capability, which uses multi-factor authentication, can be used to provide an additional layer of security. This means when someone want to delete an object, he has to provide a two-factor authentications. You can add this Multi-factor authentication delete capability to both of your bucket or object to prevent accident deleting. (It doesn't mean it is also applicable in version level, Ryan Kroonenburg didn't talk about this).

S3 versioning conclusion:

• Delete marker is a kind of version, so if you didn't enable versioning, it has nothing to do with deleting marker, you just deleted an object.

• Store all versions of an object (include all writes and even if you delete an object).

• Great backup tool.

• Once enabled, versioning cannot be disabled, only suspended (disabled).

• Integrated with Life-cycle rules.

• Multi-factor authentication (MFA) delete capability.